Helmet with air flow rib structure



FIG. 1 is a rear oblique view of a helmet with air flow rib structureshowing my new design;

FIG. 2 is a front oblique view thereof;

FIG. 3 is a top plan view thereof;

FIG. 4 is a side elevation view thereof, the opposite side being amirror image;

FIG. 5 is a front elevation view thereof;

FIG. 6 is a rear elevation view thereof; and,

FIG. 7 is a bottom plan view thereof.

The ornamental design for a helmet with air flow rib structure, as shownand described.